1. Field of the Invention
This invention relates to a solar roof member which is a solar cell integral type roofing material.
2. Related Background Art
Solar cells can be installed on roofs by methods roughly grouped into two types. One is a method in which solar cells are attached to an existing roof. The other is a method in which solar cells themselves are provided on a roof as roofing materials.
In the former, since the solar cells are installed on the existing roof by the use of some stand, conventional solar cells can be used for that purpose as they are, but they require a high cost for installation and also may give a poor appearance. Accordingly, the latter method has recently attracted notice.
With regard to the latter method, various working methods are commonly known as roofing methods from old times, which typically include hirabuki (boad roofing), tatehazebuki (standing seam roofing), namiitabuki (corrugated sheet roofing), oriitabuki (folding plate roofing), yokobuki (lateral roofing), kawaraboubuki (batten seam roofing), kawarabuki (clay tile roofing) and yousetsubuki (weld roofing) (all native terminology in Japanese own roofing). Also, as to materials for such roofing, various materials such as metals, ceramics, plastics and woods are put into use.
As known techniques making use of solar cells, various working methods have been proposed until now as disclosed in, e.g., Japanese Patent Application Laid-Open Nos. 5-18051 (slate roofing), 7-302924 (lateral roofing) and 7-211932 (batten seam roofing), and their development is on progress in variety in accordance with the various roofing methods and the quality of solar cells.
Attempts to integrally set up solar cells and roofing materials to achieve a cost reduction and an improvement in appearance are not so recently started. However, not a few methods have peculiar problems because of unique operations for lead-wire connection which must be performed when solar cell integral type roofing materials are assembled and also because of restrictions coming from the quality of solar cells and shape or design of roofing materials in the conventional solar cell integral type roofing materials. For example, in a solar cell integral type roofing material disclosed in Japanese Patent Application Laid-Open No. 7-302924 (see FIGS. 1 and 2), a space continuously extends between a sheathing roof board 21 and each roof panel 1 in the lateral direction of the roof (in the direction parallel to the ridge, i.e., in the direction crossing the direction where rain water flows, the direction vertical to the surface of the drawing) when individual solar cell integral type roofing materials are connected with one another by wiring. Wires 22 of roofing materials adjoining in the lateral direction (in the direction parallel to the ridge) can be connected through such a space. However, no space continuously extends in the flow direction of the roof (in the direction vertical to the ridge, i.e., in the direction where rain water flows), and hence the wires can not be connected therethrough. This makes it necessary to assemble the roofing materials according to the following procedure. In the following, the direction parallel to the ridge may be called "lateral direction", and the direction vertical to the ridge may be called "longitudinal direction".